ISO standards on physical environments for worker performance and productivity

An Energy Performance Evaluation of Commercially Available Window Glazing in Darwin’s Tropical Climate

A total of 40% of the world’s energy produced is utilized to maintain thermal comfort for the occupants of the building. Governments are taking measures collectively to regulate energy efficient buildings to reduce carbon emissions globally. Windows account for more than half of total energy losses in the buildings. The employment of energy efficient glazing in the construction industry is not common in Australia. This paper investigates several types of commercially available windows and their effectiveness in the hot and humid climate of Darwin. Although extensive literature is available for cold regions, these windows have not been studied in hot and humid climates such as the climate in Darwin. Building cooling loads of an academic building were calculated using Autodesk Revit Architecture and Carrier HAP. Double glazed variants offered approximately a 5% reduction in cooling loads and had a payback period of nearly 7 to 9 years, depending on the type of gas used to fill the pane cavity. The results indicate that triple glazed, or aerogel-based windows will provide about 11–12 % of energy saving in cooling loads. These can be a viable alternative and have a payback period of 11 years, while their average service life expectancy is 30 years. It was found that the feasibility of efficient glazing depends on market price, building usage, and energy efficiency of an overall building envelope.

Body mapping of regional sweat distribution in young and older males

Purpose

Given the pressing impact of global warming and its detrimental effect on the health of older populations, understanding age-related changes in thermoregulatory function is essential. Age differences in regional sweat distribution have been observed previously, but given the typically small measurement areas assessed, the development of whole body sweat maps for older individuals is required. Therefore, this study investigated age-related differences in regional sweat distribution in a hot environment (32 °C/50%RH) in young and older adults, using a body mapping approach.

Methods

Technical absorbent pads were applied to the skin of 14 young (age 24 ± 2 years) and 14 older (68 ± 5 years) males to measure regional sweat rate (RSR) at rest (30 min) and during exercise (30 min), at a fixed heat production (200 W m⁻²). Gastrointestinal (T_gi) and skin temperature (T_sk), heart rate, thermal sensation, and thermal comfort were also measured.

Results

Whole body sweat maps showed that despite equal heat production, healthy older males had significantly lower gross sweat loss (GSL) than the young and significantly lower RSR at almost all body regions at rest and at the hands, legs, ankles, and feet during exercise. The lower sweat loss in the older group coincided with a greater increase in T_gi and a consistently higher T_sk at the legs, despite subjectively feeling slightly cooler than younger individuals.

Conclusion

These findings support the evidence of age-related deterioration in both autonomic and subjective responses in the heat and highlight the lower extremities as the most affected body region.

Electronic supplementary material

The online version of this article (10.1007/s00421-020-04503-5) contains supplementary material, which is available to authorized users.

From Office Environmental Stressors to Work Performance: The Role of Work Patterns

Background: Different studies have shown a relationship between office environmental stressors and performance. However, studying environmental stress in the workplace requires analyzing more specific patterns to generate knowledge about the type of employees who are more or less vulnerable to environmental stressors. The present study analyzes the mediating role of health symptoms and negative emotions in the relationship between stressors and performance in different work patterns (task complexity and interactivity). Methods: There were 83 office workers (n = 603 time points) that took part in a diary study with multilevel design. Results: The appraisal of the environmental stressors is positively related to health-related symptoms, which in turn increase negative emotions, and then decrease the performance of workers who perform complex tasks and interact frequently with other people at work. This mediation is not significant when office workers do not interact frequently with other people at work and/or perform simple, rather than complex tasks. Conclusions: Work patterns play an important role when studying the mediating role of health-related symptoms and negative emotions in the relationship between the appraisal of environmental stressors and performance in office workers. In other words, employees in the 'interactive and complex' pattern are more vulnerable to the negative effects of office stressors on performance.

The association between wet-bulb globe temperature and other thermal indices (DI, MDI, PMV, PPD, PHS, PSI and PSIhr): a field study

The current study aimed at comparing the correlation coefficients between wet-bulb globe temperature (WBGT) and a number of parameters, including the discomfort index (DI), modified discomfort index (MDI), predicted mean vote (PMV), predicted percentage of dissatisfaction (PPD), predicted heat strain (PHS), physiological strain index (PSI) and physiological strain index heart rate (PSI_hr). In total, 30 workers of a pelletizing factory participated in this study. Environmental parameters and workers' physiological parameters were measured in 10 working stations. The results showed that effective WBGT (WBGT_eff) strongly correlates with DI, MDI, PMV, PPD, PHS, PSI and PSI_hr. WBGT_eff had the highest correlation coefficients with PMV, MDI, PHS and PSI_hr. Based on the obtained results, it was concluded that heat stress exceeded the standard limit for a number of indices in some of the working stations. Thus, some controlling measures should be taken to reduce heat stress in these stations.